This invention relates to interior base materials suitable for a pigment ink printing process, interior base materials printed with a pigment printing ink which have fastness, that is, excellent waterproof, weatherproof and abrasion resistance property, and the methods of printing interior base materials. More specifically, the present invention relates to interior base materials which provide good printed images with sharpness to the inner part of the material by applying a pigment ink by such means as ink-jet printing or gravure printing, and the printing methods thereof.